Bombus ruderatus
Field bumblebee (Bombus ruderatus )
The field bumblebee (Bombus ruderatus ) is a rare hummelart, which is native to Europe from the Iberian Peninsula to the southern Fennoscandia and throughout Germany. The field Hummel lives in colonies of 50 to 100 insects.
Features
The females of the field bumblebees are 21 to 24 millimeters long, while the males reach 15 to 17 millimeters, and the workers even measure only 11 to 18 millimeters. The spans of the wings reach 40-43 mm in females, 30 to 33 mm in males and 21 to 35 millimeters for the workers. Head like proboscis that reaches 8 to 10 mm in females 12 to 13 millimeters, with the males 8 to 10 mm and of the workers, as compared with other species of bumblebee very long. In the color scheme is similar to the field Hummel the Garden (B. hortorum ) and the Tonerdhummel (B. argilaceus ). On the chest is on the head side facing a yellowish brown, wide strip. That, however, is missing in some individuals or is less pronounced. Also located at the rear end of the thorax and on the first tergites of the abdomen one more binding. The tergites 5 and 6 have a white fur.
Way of life
The habitat of this hummelart are open landscapes, especially meadows, pastures, embankments and ditches. The main honey plants of polylectic animals are arable woundwort, broad beans, red clover, motherwort, nettles Black, white clover, vetch, pea - Veneta, comfrey, Fireweed. Flight time of univoltinen type begins in late April with the overwintered females. The first males occur in mid-July and the end of July following first young females. According to the Red List of bees of Germany it is (assuming risk, status unknown) in the G category classified.
In 1982, she was deliberately introduced in Chile in order to provide pollination work. Meanwhile, she spreads invasively on the South American landmass.
Reproduction
The propagation usually takes place in nests of mice and thus underground in the box Hummel. The nests in part from the Bearded cuckoo bumblebee (Bombus barbutellus ) are parasitized.